Incompatible Changes
  ====================

  * The choose-list command has been removed.
  * 'terminal-overrides' is now a server option, not a session option.
  * 'message-limit' is now a server option, not a session option.
  * 'monitor-content' option has been removed.
  * 'pane_start_path' option has been removed.
  * The "info" mechanism which used to (for some commands) provide feedback
    has been removed, and like other commands, they now produce nothing on
    success.